hyperactor_mesh_test_bootstrap: enable logging (#755)

Summary:
Pull Request resolved: #755

using `ProcessAllocator` in `hyperactor_mesh` testing, we need this to get logs.

Reviewed By: mariusae

Differential Revision: D79594721

fbshipit-source-id: 88706b318742062210ff39106aa3e325e63a26e0

Author: shayne-fletcher

hyperactor_mesh/test/bootstrap.rs

@@ -10,5 +10,11 @@
 /// simply invoking [`hyperactor_mesh::bootstrap_or_die`].
 #[tokio::main]
 async fn main() {
+    // Logs are written to /tmp/$USER/monarch_log*.
+    let subscriber = tracing_subscriber::fmt()
+        .with_env_filter(tracing_subscriber::EnvFilter::from_default_env())
+        .finish();
+    tracing::subscriber::set_global_default(subscriber).expect("failed to set subscriber");
+
     hyperactor_mesh::bootstrap_or_die().await;
 }